Re: [PATCH] kernel-fitimage: dtb sections named by their filenames and one config section for each dtb

I added some .dtso overlay files to KERNEL_DEVICETREE in order to have them added to my fitimage file through the kernel-fitimage.class.

This seems to work, as long as corresponding .dtso files are added to the right subdir with SRC_URI in the linux kernel recipe. The dtbo becomes included in the fitimage. config sections are emitted.

However, the config sections in the fitimage become weird. One config section is emitted for each dtb or dtbo file. Does this make sense? Shouldn't there be one config section for each .dtb file, and then dtbo references be added to these sections? The most simple alternative would be to add every .dtbo file in KERNEL_DEVICETREE to ever .dtb config section, but probably there should be some way to select which overlays to add to each dtb.

It currently looks like this:
```
        configurations {
                default = "conf-rk3588s-rock-5a.dtb";
                conf-rk3588s-rock-5a.dtb {
                        description = "1 Linux kernel, FDT blob";
                        
                        kernel = "kernel-1";
                        fdt = "fdt-rk3588s-rock-5a.dtb";
                        
                        
                        
                        hash-1 {
                                algo = "sha256";
                        };
                };
                
                conf-rock-5a-radxa-camera-4k.dtbo {
                        description = "0 FDT blob";
                        
                        
                        fdt = "fdt-rock-5a-radxa-camera-4k.dtbo";
                        
                        
                        
                        hash-1 {
                                algo = "sha256";
                        };
                };
        };
```
but I would have expected it to look like this:
```
        configurations {
                default = "conf-rk3588s-rock-5a.dtb";
                conf-rk3588s-rock-5a.dtb {
                        description = "1 Linux kernel, FDT blob";
                        
                        kernel = "kernel-1";
                        fdt = "fdt-rk3588s-rock-5a.dtb", "fdt-rock-5a-radxa-camera-4k.dtbo";;
                        
                        
                        
                        hash-1 {
                                algo = "sha256";
                        };
                };
        };
```

As in this example from u-boot/doc/uImage.FIT/overlay-fdt-boot.txt:
```
	/dts-v1/;
	/ {
		images {
			kernel {
				data = /incbin/("./zImage");
				type = "kernel";
				arch = "arm";
				os = "linux";
				load = <0x82000000>;
				entry = <0x82000000>;
			};
			fdt-1 {
				data = /incbin/("./foo.dtb");
				type = "flat_dt";
				arch = "arm";
				load = <0x87f00000>;
			};
			fdt-2 {
				data = /incbin/("./reva.dtbo");
				type = "flat_dt";
				arch = "arm";
				load = <0x87fc0000>;
			};
			fdt-3 {
				data = /incbin/("./revb.dtbo");
				type = "flat_dt";
				arch = "arm";
				load = <0x87fc0000>;
			};
			fdt-4 {
				data = /incbin/("./bar.dtbo");
				type = "flat_dt";
				arch = "arm";
				load = <0x87fc0000>;
			};
			fdt-5 {
				data = /incbin/("./baz.dtbo");
				type = "flat_dt";
				arch = "arm";
				load = <0x87fc0000>;
			};
		};

		configurations {
			default = "foo-reva.dtb;
			foo-reva.dtb {
				kernel = "kernel";
				fdt = "fdt-1", "fdt-2";
			};
			foo-revb.dtb {
				kernel = "kernel";
				fdt = "fdt-1", "fdt-3";
			};
			foo-reva-bar.dtb {
				kernel = "kernel";
				fdt = "fdt-1", "fdt-2", "fdt-4";
			};
			foo-revb-bar.dtb {
				kernel = "kernel";
				fdt = "fdt-1", "fdt-3", "fdt-4";
			};
			foo-revb-baz.dtb {
				kernel = "kernel";
				fdt = "fdt-1", "fdt-3", "fdt-5";
			};
			foo-revb-bar-baz.dtb {
				kernel = "kernel";
				fdt = "fdt-1", "fdt-3", "fdt-4", "fdt-5";
			};
			bar {
				fdt = "fdt-4";
			};
			baz {
				fdt = "fdt-5";
			};
		};
	};
```